Having seen that for type I superconformal symmetry the Casimir operator differs form the spinning bosonic one by a nilpotent piece \(A\) , our strategy is to treat \(A\)  as a perturbation and construct supersymmetric partial waves as a perturbation of spinning partial waves. Since \(A\)  is nilpotent, the process will produce exact results at some finite order \(N\le \dim \mathfrak {g}_{(1)}/2\) . General methods to solve for eigenfunctions of a Hamiltonian \(H= H_0 + A\)  in terms of those of \(H_0\)  are well established. Particularly suited for our purposes is the exposition of Messiah, [1]}, that we now review. For simplicity, we assume that \(H\)  and \(H_0\)  have discrete spectra and finite dimensional eigenspaces. By a limiting process, the construction can be extended to more general spectra.
